I just read of an interesting theory that the Cambrian Explosion
was touched off by the evolution of eyes in a prototrilobite. The new
animals, with imaging optics, became such efficient predators that
animals had to develop both hard parts and eyes of their own to
successfully ward them off. So the development of eyes in arthropods
generated new types of predation that caused an increase in animal
diversification.
The fellow who developed this theory points out that trilobites
were the among both the first animals to have hard partsand the first
animals to show eyes, early in the Cambrian. Other phyla didn't leave
fossils of eyes until much later, near the end of the Ordivician and
maybe even during the Silurian. Arthropods other than trilobites
develop eyes, although much later than trilobites. So trilobites eyes
touched off the explosion in diversity at the beginning of the
Cambrian.
However, I have a problem with this theory. Can any help me with
this?
As far as I know, trilobites do not show signs of being efficient
predators. At least not of animals comparable in size, the ones
trilobites could most likely see. Why would the development of ...